Surface effect vehicles are used for moving just above water, ground, or a combination of terrains, making them more efficient than either a water vehicle, like a boat, or a ground vehicle, like an automobile. This is because when a vehicle is in contact with a water or ground surface there is a large coefficient of friction between the vehicle and the surface. However, when a vehicle moves through a medium such as air, the coefficient of friction is substantially reduced. Surface effect vehicles ride on cushions of air just above a surface, like water, wherein the friction-reducing cushion enhances the ability of the surface effect vehicle to move forwardly.
There is an acknowledged difference between flying aircraft and surface effect vehicles. Flying aircraft use the low pressure flow of air over the aircraft wing and the high pressure flow of air beneath the wing to create lift. In contrast, surface effect vehicles use the high pressure of air beneath an air foil to produce a cushion of air between the vehicle and a traversed surface to separate the vehicle from the surface. Forward movement of the surface effect vehicle is from some type of propulsion means.
In essence, surface effect vehicles cannot rise more than a few feet from the surface without redesigning the air foil and providing an elevator. To date, there have been stabilization problems for surface effect vehicles designed to operate both as a boat and as a surface effect vehicle. When departing one medium for another the hydrodynamic and aerodynamic forces on the vehicle are often difficult to control and stabilize. Some vehicles use air flaps on the rear of the vehicle to provide control and stabilization. Such arrangements are found in U.S. Pat. Nos. 3,918,382, 4,151,893 and 4,712,630.
Another problem surface effect vehicles have is that it takes a great deal of power to-accelerate the surface effect vehicle to a sufficient speed so that the air pressure beneath the surface effect vehicle will lift the vehicle free of the surface to be traversed. This again is due to the relatively large coefficient of friction between the moving surface effect vehicle and the surface to be traversed as compared to the resistance offered between just air and the vehicle.
The present invention meets the need for a stable surface effect vehicle while also overcoming the problem of freeing the surface effect vehicle from the surface to be traversed.